Eating seafood can help prevent heart attacks and strokes, can lower blood pressure and may even help ward off depression. Regular fish consumption reduces the risk of heart attack by as much as 40 percent. Seafood's magic ingredient: omega-3 fatty acids. Fatty fish, like salmon (fresh and canned), tuna (fresh and canned), herrings, trout, mackerel and sardines, are loaded with these beneficial fats. Just be careful with cooking; pan-frying and deep-frying at high temperatures can destroy omega-3 fats.
All fish supply high amounts of protein, have low levels of saturated fat and contain vitamin E, an important antioxidant. Seafood benefits people with diabetes, can contribute calcium (from the small, soft bones in some fish) to one's diet, and may reduce the risk of asthma in children. It is also low in calories, depending on how it's prepared.
Some people shy away from shellfish because it can be high in cholesterol, but cholesterol in food does not directly transfer to cholesterol in blood. Although it is important to limit the amount of cholesterol you eat, especially if you have diabetes or heart disease, saturated and trans fats are more detrimental to serum (blood) cholesterol than the cholesterol in shellfish. If you are trying to lower your blood cholesterol, focus on replacing saturated fats with healthy fats, adding fiber and exercising, instead of counting cholesterol milligrams.
Mercury remains a concern with seafood. Some larger fish, like shark, swordfish and marlin, contain this metal that can cause brain and nerve damage. Pregnant women and small children should avoid these fish, and others should limit their consumption to once per week. Fortunately, the fish highest in healthful omega-3 fats are the lowest in mercury.